Newark Castle is far more than the structure you see on the surface. What appears to be a riverside ruin is, in reality, a multi‑level architectural system built into the geology of a modest cliff above the Trent. The Castle extends “underground” — or more accurately, into itself — through chambers, an undercroft, and internal voids designed with purpose, not accident.

As Project works progress, these hidden spaces will finally become legible. The unseen Castle is about to be seen. I had the privilege of exploring these areas recently, and here is what I found.

The North‑West Tower: A Corridor to Misunderstood Rooms

Between the north‑west tower and the Gatehouse, a narrow corridor descends gently within the wall, leading down a flight of stairs to two trapdoors. Each opens onto a ladder descending into enclosed rooms long referred to as “dungeons”. The term is misleading. The Castle’s public‑facing material does not name these rooms at all — a sensible decision, given that the historical record offers no evidence of their use as prisons. Scholars avoid over‑interpreting such spaces, and even what I write here may one day be scrutinised by future historians.

The rooms themselves are well‑built, dry, and stable. One carries the distinct footprint of an ice house — cool, proportionate, and neatly engineered. The other has a more uneven floor but is still a deliberate architectural space. Access is extremely tight: one ladder requires a neat twist of the body to align knees within the confined opening.

These are not crude holes. They are part of the Castle’s internal fabric.

The stairs to the ladders to the underground rooms

The Debtors’ Prison: A Different Story Entirely

You might have visited a prison is the far tower (South East) at the opposite end of the Castle — described as a debtors’ prison. This was a civic institution, not a medieval one.

Debtors’ prisons were paradoxical places. A person who owed money could be confined until the debt was paid, yet they were often the only individual capable of earning the money required for release. Families frequently had to sell goods or borrow from neighbours to secure freedom. It was a system that punished poverty by deepening it.

This room is accessed by a conventional flight of stairs — simple, direct, and surprisingly easy to navigate. Its barrel‑vaulted ceiling of rougher, unfinished stone reflects its later, utilitarian purpose.

The room used for the ‘debtors prison’ in earlier days, complete with barrel vaulted ceiling of rougher, unfinished stone.

Not Subterranean — But Inside the Castle’s Fabric

None of these so‑called underground areas are truly subterranean. They sit within the thickness of the curtain wall, built across the natural cliff that overlooks the River Trent. Medieval engineers used the geology to create internal chambers that were cool, secure, and structurally efficient — without excavating below ground level.

This is why the Castle feels taller from the riverbank than it does from the interior. You are walking above rooms you cannot see.

The north‑west tower rooms follow this logic: access via a trapdoor reached by a well‑built stair, then a ladder into beautifully constructed, dry, stable chambers — one ice‑house‑like, the other more uneven but still proportionate and intentional.

Looking down from the mediaeval loos to the trapdoors leading to the ‘underground’ spaces.

The Undercroft: The Castle’s Hidden Masterpiece

The undercroft is the most impressive of all. It sits at what is technically ground level, yet feels subterranean because of the height difference between the Castle interior and the riverbank.

It is barrel‑vaulted, ecclesiastical in nature, with a column‑and‑pier arrangement built in the Romanesque style shared with the Gatehouse. Steps lead down into a large, structured space. From the undercroft, the stairs continue directly to Trent's edge.

It is disorientating: you enter the Castle at one height, descend into a chamber, and then exit at the foot of the Castle. Only when you later walk along the curtain wall and look down at the river do you realise you were effectively standing on the roof of the undercroft.

It is a masterclass in medieval engineering, and one of the Castle’s most compelling hidden features. It currently hosts the Castle’s stored odds and ends, and I defer to previous photographs of this beautiful space.

Used with permission - ©John McVeigh.  Showing the almost church-like vaulting of this beautiful space.

Graffiti, Squatters, and Marks of Meaning

The internal walls contain layers of human presence. Graffiti ranges from unfortunate modern felt‑tip interventions to witch marks — apotropaic symbols carved to ward off evil spirits. These are common in East Midlands churches and are distinct from masons’ marks, which identify a craftsman’s work for payment.

Each mark is a fragment of Newark’s long, complex story.

Look carefully to see examples of graffiti which adorn the internal walls of the Castle

Why Accuracy Matters Here

The unseen Castle is often misunderstood. Words like dungeon and underground create myths that obscure the real architectural intelligence of the site. Newark Castle was built with depth, intention, and structural sophistication. Its lower chambers are not necessarily instruments of punishment but components of a defensive, geological, and domestic system.

By describing these spaces accurately, we reveal a Castle that is not just a picturesque ruin, but a multi‑level medieval structure with secrets in its walls — secrets that will be brought back into public understanding in future Guided Tours.

The Castle Beneath the Castle

The Castle’s hidden spaces contain layers of human presence: medieval engineering, post‑medieval occupation, Victorian curiosity, and modern mischief. Newark Castle is more than what you see. It is what lies beneath — and within.

As the Gatehouse Project works continue, these hidden spaces will form part of the visitor experience, allowing people to explore areas closed for generations. The unseen Castle will finally be seen, and its architectural story will be complete.